The Indian Ocean (IO) extends over 30% of the global ocean area and is rimmed by 36 littoral and 11 hinterland nations sustaining about 30% of the world's population. The landlocked character of the ocean along its northern boundary and the resultant seasonally reversing wind and sea surface circulation patterns are features unique to the IO.

A Southern Ocean Pilot cruise covering the latitudes from 10°N to 56°S in the open Indian Ocean was car-
ried out during January–February 2004. Surface and upper air data collected during this cruise are re-
ported here. It is shown that the broad features of the atmosphere, in particular that of temperature, follow

Extensive measurements of columnar aerosol optical depth (AOD), composite (MT) and black carbon aero-
sol mass (MB) concentrations were made over the tropical Indian and Southern Oceans as a part of the
Pilot Expedition to the Southern Ocean during the boreal winter. The AOD, MT and MB show large lati-

Stable isotope (? 18O and ? D) and salinity measurements were made on the surface waters collected from the Southern Indian Ocean during the
austral summer (25 January to 1 April 2006) onboard R/V Akademik Boris Petrov to study the relative dominance of various hydrological processes, viz. evaporation, precipitation, melting and freezing over different latitudes.

Polymetallic nodules found on the deep seafloor (>4000 m water depth) have been recognized as an alternative source for certain metals, when land deposits get exhausted.